Mutagenicity of Selected Chemicals in the Mammalian Spot Test

Abstract

The spot test is an in vivo method for the detection of genetic alterations, including point mutations, in somatic cells of mice. Mouse embryos which are heterozygous for different recessive coat-color genes are treated in utero at one or more stages between days 7 and 11 postconception by injection of a mutagen into the peritoneal cavity of the mother animal or by other appropriate routes of administration. If this treatment leads in a pigment precursor cell to an alteration of the wild-type allele of one of the genes under study or to its loss, a color spot in the adult coat may be seen. As each mouse observed represents many treated embryonic cells in which a mutation could have occurred, and as the whole spectrum of chromosome damage and DNA-alterations should be covered, this method is sensitive to mutagens of all types of action.